As promised, the National Highway Traffic Safety Administration (NHTSA) looked into the safety of lithium batteries after a Chevrolet Volt caught fire back in May. After conducting three different tests two weeks ago, the NHTSA found that the Volt's battery either caught fire or began to smoke in two out of the three.

General Motors Co.'s Chevrolet Volt underwent several tests in a NHTSA Wisconsin facility earlier this year. On May 12, 2011, it experienced the side-impact crash test. Three weeks later, the plug-in electric vehicle (EV) caught fire while parked in the NHTSA testing center.

The fire, which was fierce enough to burn other vehicles parked nearby, prompted an investigation of the Chevrolet Volt and the safety of lithium batteries.

The NHTSA conducted side-impact crash tests for the Chevrolet Volt on November 16, 17 and 18. After each test, the batteries of the three separate Volts were then rotated 180 degrees. Out of the three tests, two resulted in fire, smoke or sparks while one remained normal.

The November 16 test had normal results, while the November 17 test led to a battery fire one week later and the November 18 test caused the battery to smoke and emit sparks. The battery packs of the three Volts were not drained after any of the crashes.

The results have led to a formal investigation of the safety of the Chevrolet Volt and its lithium battery.

"While it is too soon to tell whether the investigation will lead to a recall of any vehicles or parts, if NHTSA identifies an unreasonable risk to safety, the agency will take immediate action to notify consumers and ensure that GM communicates with current vehicle owners," said NHTSA.

GM has said that it launched a system where first responders immediately depower the battery of a Chevrolet Volt after a severe crash. This is safety protocol because lithium batteries can catch fire if the internal cells or the battery case are pierced by steel or another ferrous metal. Even the slightest piercing of the battery can lead to a reaction days or weeks later.

"The Volt is safe and does not present undue risk as part of normal operation or immediately after a severe crash," said GM after the NHTSA's tests this month. "GM and the agency's focus and research continue to be on battery performance, handling, storage and disposal after a crash or other significant event, like a fire, to better serve first- and secondary-responders."

NHTSA and GM have both said that they are unaware of any battery-related fires caused by roadway crashes involving customers. However, NHTSA advised EV owners to remain cautious in the event of a crash as they would in a gasoline or diesel-fueled vehicle. The NHTSA's advice includes stepping out of the car and moving away from it while contacting authorities. When responders arrive, they are to check for markings that it is an EV and use large amounts of water on the vehicle if there are any signs of a fire. They are to then contact experts at the vehicle's manufacturer on how to discharge a propulsion battery.

There are currently 6,000 Volt owners on the roads, but the number of EVs cruising around in the U.S. is expected to increase because U.S. President Barack Obama is looking to put 1 million EVs on the roads by 2015.

quote: ...its irresponsible for the NHTSA to release information like this, without knowing what the full story is, and without knowing if there's really a defect with the Volt, or if just different safety protocol...

Nonsense, they have a duty to report these things.

As for them not knowing what the "defect" is, there is no defect, this is just how the batteries are, and yes, there needs to be some protocol for EVs.

As far as the headline "Volt BURSTS INTO FLAMES", how many stories have you seen about Prius batteries up in flames? Certainly there are many more out there than this and they have been involved in accidents. Don't know if all Priuses have Lithium batteries or not, but it seems that this is more of a issue with GM engineering. Typical GM stuff...

The stabdard hybrid battery on a Prius is a 200v NiMH battery pack. There are some third-parties who will convert a Prius into a Plug-in Hybrid using lithium batteries but those are few and far between. Toyota has made the 2010+ models able to be plug-ins from the factory but I have yet to hear of any being availible in the states.

That said the amount of energy stored in the prius battery is far lower and because of the how the hybrid drive works in the Prius the battery is rarely in a state of "full charge". That said shorting any good sized charged battery can lead to fires in the right circumstances. It is just that some lithium cell types can do it all on their own if they are not handled or maintained correctly.

IMHO the real answer if we are serious about moving to electric vehicles is to move to "magnetic resonance" style charging/power in the toll roads to start and move it out from there. That would leave the battery to deal with acceleration, regenerative breaking, and "off grid" or "down" roads. Heck I suspect you could sneak some data over that power link, thus allowing cars and the road itself to comunicate to reroute around trouble or automate driving.